JP6043773B2 - Sheet metal processing method using direct diode laser light and direct diode laser processing apparatus for executing the same - Google Patents

Description

  The present invention relates to a sheet metal processing method using a direct diode laser beam and a direct diode laser processing apparatus for executing the method.

  2. Description of the Related Art Conventionally, as a laser processing apparatus for processing a sheet metal, an apparatus using a carbon dioxide (CO2) laser oscillator, a YAG laser oscillator, or a fiber laser oscillator as a laser light source is known. The fiber laser oscillator has advantages such as better light quality and extremely high oscillation efficiency than the YAG laser oscillator. For this reason, a fiber laser processing apparatus using a fiber laser oscillator is used for industrial purposes, particularly for sheet metal processing (cutting or welding).

  Further, in recent years, a laser processing machine using a direct diode laser (DDL) module as a laser light source has been developed. The DDL module superimposes multiple-wavelength laser light generated by a plurality of laser diodes (LD) and transmits the laser light to the processing head using a transmission fiber. Then, the laser light emitted from the end face of the transmission fiber is condensed and irradiated on a workpiece (work) by a collimator lens, a condensing lens, or the like.

  By the way, in laser processing, in order to suppress the occurrence of dross, the focal point of the laser beam is positioned above the workpiece cutting position so that the cutting width is approximately one half of the workpiece plate thickness. A cutting method for focusing is known (Patent Document 1).

JP-A-11-170077

  However, in patent document 1, dross generation | occurrence | production suppression was not yet enough.

  Moreover, in the conventional laser processing machine, the case where it processes using a multi-wavelength laser beam was not examined concretely.

  The present invention has been made in view of the above problems, and its purpose is to provide a sheet metal that has less dross adhesion and easily peels off the attached dross when performing sheet metal processing using multi-wavelength laser light. It is providing the laser processing method of this, and the laser processing machine which performs this.

  One embodiment of the present invention is a method of cutting a sheet metal having a thickness of 2 mm or more, having a focal length f ≧ 150 mm, and a focal position Pf with −2.0 mm <Pf ≦ about 0.0 with respect to the upper surface of the sheet metal. The sheet metal is irradiated with laser light from a DDL module using a condensing lens arranged at mm.

  The sheet metal is preferably an aluminum sheet metal.

  The gas pressure of the assist gas supplied to the processing point during the processing is preferably 1.5 MPa (megapascal) or more.

  The sheet metal preferably has a thickness of 100 mm or less.

  Preferably, the laser light from the DDL module is composed of at least two or more multiple-wavelength laser lights, and the wavelength of any laser light is less than 1000 nm.

  Preferably, the wavelength (Wavelength) of the laser beam from the DDL module is configured to be a multiple-wavelength of 800 nm to 990 nm.

  Preferably, the BPP (Beam parameter product) of the laser light emitted from the DDL module is 7 mm * mrad or more and 20 mm * mrad or less.

Preferably, the BPP (Beam parameter product) of the laser beam is 10.3 mm * mrad. Preferably, the Beam waist diameter is 150 μm or more and 370 μm or less.

  Preferably, the beam waist diameter is not less than 300 μm and not more than 364 μm.

  Preferably, the focal lens has an incident diameter of 20 mm and a condensing diameter d of 300 μm to 364 μm.

  Preferably, the Rayleigh length of the laser light is 1.5 mm or more and 6 mm or less.

  Preferably, the Rayleigh length of the laser light is 2.2 mm or more and 3.4 mm or less.

  Another aspect of the present invention is a method of cutting a sheet metal having a thickness of less than 2 mm, the focal length f being f ≦ 120 mm, and the focal position Pf being 0.0 mm <Pf ≦ 2 with respect to the upper surface of the sheet metal. The sheet metal is irradiated with laser light from a DDL module using a condenser lens arranged at 0.0 mm.

  The sheet metal is preferably an aluminum sheet metal.

  In the processing, the gas pressure of the assist gas supplied to the processing point is preferably 0.8 MPa to 1.5 MPa.

  Preferably, the laser light from the DDL module is composed of at least two or more multiple-wavelength laser lights, and the wavelength of any laser light is less than 1000 nm.

  Preferably, the wavelength (Wavelength) of the laser beam from the DDL module is configured to be a multiple-wavelength of 800 nm to 990 nm.

  Preferably, the BPP (Beam parameter product) of the laser light emitted from the DDL module is 7 mm * mrad or more and 20 mm * mrad or less.

Preferably, the BPP (Beam parameter product) of the laser beam is 10.3 mm * mrad. Preferably, the Beam waist diameter is 150 μm or more and 370 μm or less.

  Preferably, the beam waist diameter is not less than 300 μm and not more than 364 μm.

Preferably, the incident diameter of the focus lens is a diameter of 300 μm or more and 364 μm or less. Preferably, the Rayleigh length of the laser light is 1.5 mm or more and 6 mm or less.

  Preferably, the Rayleigh length of the laser light is 2.2 mm or more and 3.4 mm or less.

According to still another aspect of the present invention, when cutting a sheet metal having a thickness of 2 mm or more, it has a focal length f ≧ 150 mm, and the focal position Pf is defined as −2.0 mm <Pf ≦ about with respect to the upper surface of the sheet metal. Using a condensing lens disposed at 0.0 mm, the sheet metal is irradiated with parallel laser light from a DDL module,
When cutting a sheet metal having a thickness of less than 2 mm, a condenser lens having a focal distance f of f ≦ 120 mm and a focal position Pf of 0.0 mm <Pf ≦ 2.0 mm with respect to the upper surface of the sheet metal is used. It is used to irradiate the sheet metal with the parallel laser light from the DDL module.

  In this aspect, when cutting a sheet metal having a thickness of 2 mm or more, the conditions described after the first aspect are preferably satisfied. When cutting a sheet metal having a thickness of less than 2 mm, the second It is preferred that the conditions described after the embodiment are satisfied.

Still another aspect of the present invention includes a DDL module that oscillates multi-wavelength laser light, a transmission fiber that transmits multi-wavelength laser light from the DDL module, and multi-wavelength laser light transmitted by the transmission fiber. A laser processing machine for focusing and processing sheet metal,
When cutting a sheet metal having a thickness of 2 mm or more, a condensing lens having a focal length f ≧ 150 mm and a focal position Pf arranged at −2.0 mm <Pf ≦ about 0.0 mm with respect to the upper surface of the sheet metal is used. The sheet metal is irradiated with parallel laser light from the DDL module.

Still another aspect of the present invention includes a DDL module that oscillates multi-wavelength laser light, a transmission fiber that transmits multi-wavelength laser light from the DDL module, and multi-wavelength laser light transmitted by the transmission fiber. A laser processing machine for focusing and processing sheet metal,
When cutting a sheet metal having a thickness of less than 2 mm, a condenser lens having a focal distance f of f ≦ 120 mm and a focal position Pf of 0.0 mm <Pf ≦ 2.0 mm with respect to the upper surface of the sheet metal is used. It is used to irradiate the sheet metal with the parallel laser light from the DDL module.

Still another aspect of the present invention includes a DDL module that oscillates multi-wavelength laser light, a transmission fiber that transmits multi-wavelength laser light from the DDL module, and multi-wavelength laser light transmitted by the transmission fiber. A laser processing machine for focusing and processing sheet metal,
When cutting a sheet metal having a thickness of 2 mm or more, a condensing lens having a focal length f ≧ 150 mm and a focal position Pf arranged at −2.0 mm <Pf ≦ about 0.0 mm with respect to the upper surface of the sheet metal. And irradiating the sheet metal with a parallel laser beam from a DDL module,
When cutting a sheet metal having a thickness of less than 2 mm, a condenser lens having a focal distance f of f ≦ 120 mm and a focal position Pf of 0.0 mm <Pf ≦ 2.0 mm with respect to the upper surface of the sheet metal is used. It is used to irradiate the sheet metal with the parallel laser light from the DDL module.

  According to the present invention, when processing is performed using multi-wavelength laser light, the attached state of dross is small, and the attached dross is easily peeled off.

It is a perspective view which shows an example of the laser processing machine which concerns on embodiment of this invention. FIG. 2A is a side view showing an example of a laser oscillator according to the embodiment of the present invention. FIG. 2B is a front view of the laser oscillator. It is the schematic which shows an example of the LD module which concerns on embodiment of this invention. It is a photograph figure which shows the light dross in an aluminum cut surface. It is a photograph figure which shows the normal dross in an aluminum cut surface. It is a photograph figure which shows the heavy dross in an aluminum cut surface. It is a table | surface which shows the test result of Example 1 of this invention. It is a table | surface which shows the test result of Example 2 of this invention. It is a table | surface which shows the test result of Example 3 of this invention. It is a table | surface which shows the test result of the comparative example 1 of this invention.

  Embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals.

  FIG. 1 shows an overall configuration of a DDL laser beam machine according to an embodiment of the present invention. As shown in the figure, the DDL laser beam machine according to the embodiment includes a laser oscillator 11 that oscillates a multi-wavelength laser beam LB, and a transmission fiber (process fiber) that transmits the laser beam LB oscillated by the laser oscillator 11. ) 12 and a laser processing machine (laser processing machine main body) 13 for condensing the laser beam LB transmitted by the transmission fiber 12 to a high energy density and irradiating the workpiece (work) W.

  The laser processing machine 13 has a processing head 17 that irradiates the workpiece with the laser beam LB emitted from the transmission fiber 12. The processing head 17 includes a collimator unit 14 that converts laser light from the fiber 12 into substantially parallel light by a collimator lens 15, and a laser light LB that has been converted to substantially parallel light, perpendicular to the X-axis and Y-axis directions. A bend mirror 16 that reflects downward in the Z-axis direction, a condensing lens 18 that condenses the laser light LB reflected downward by the bend mirror 16, and a nozzle at the tip. As the collimator lens 15 and the condenser lens 18, for example, a general lens such as a quartz plano-convex lens can be used.

  Although not shown in FIG. 1, a lens driving unit that drives the collimator lens 15 in a direction parallel to the optical axis (X-axis direction) is installed in the collimator unit 14. The laser processing machine further includes a control unit that controls the lens driving unit.

  The laser processing machine 13 further includes a processing table 21 on which a workpiece (work) W is placed, a portal X-axis carriage 22 that moves in the X-axis direction on the processing table 21, and an X-axis carriage 22. And a Y-axis carriage 23 that moves in the Y-axis direction perpendicular to the X-axis direction. The collimator lens 15 in the collimator unit 14, the bend mirror 16, and the condensing lens 18 in the processing head 17 are fixed to the Y-axis carriage 23 in a state where the optical axis has been adjusted in advance. Move in the axial direction. It is also possible to provide a Z-axis carriage that can move in the vertical direction with respect to the Y-axis carriage 23 and to provide the condenser lens 18 on the Z-axis carriage.

  The laser processing machine according to the embodiment of the present invention irradiates the workpiece W with the laser beam LB having a predetermined condensing diameter which is condensed by the condenser lens 18 and also injects an assist gas coaxially to melt the melt. While removing, the X-axis carriage 22 and the Y-axis carriage 23 are moved. Thereby, the laser beam machine can cut the workpiece W. Examples of the workpiece W include various materials such as stainless steel, mild steel, and aluminum. The plate thickness of the workpiece W is, for example, about 0.1 mm to 100 mm.

  2 and 3 show details of the laser oscillator 11. 2A and 2B, the laser oscillator 11 includes a housing 60, the LD module 10 housed in the housing 60 and connected to the transmission fiber 12, and the housing 60. A power supply unit 61 that is housed in the LD module 10 and supplies power to the LD module 10, a control module 62 that is housed in the housing 60 and controls the output of the LD module 10, and the like are provided. An air conditioner 63 that adjusts the temperature and humidity in the housing 60 is installed outside the housing 60.

As shown in FIG. 3, the LD module 10 superimposes and outputs laser beams having multiple wavelengths (λ1, λ2, λ3,..., Λn). The LD module 10 includes a plurality of laser diodes (hereinafter referred to as “LD”) 3 ₁ , 3 ₂ , 3 ₃ ,... 3 _n (n is an integer of 4 or more), and LD 3 ₁ , 3 ₂ , 3 _3. , · · · _{3 n} to the fiber _{4 1,} 4 2, _{4 3,} is connected via a · · · _{4 n,} multiwavelength λ1, λ2, λ3, ···, spectral beam combination to laser light of λn A spectral beam combining unit 50 that performs (spectral beam combining) is provided.

As the plurality of LD3 ₁ , 3 ₂ , 3 ₃ ,... 3 _n , various semiconductor lasers can be adopted, and the combination of types and numbers is not particularly limited, and is appropriately selected according to the purpose of sheet metal processing. Is possible. The wavelengths λ1, λ2, λ3,..., Λn of LD3 ₁ , 3 ₂ , 3 ₃ ,... 3 _n are selected, for example, to be less than 1000 nm, selected in the range of 800 nm to 990 nm, or 910 nm to 950 nm. However, in this embodiment, it is set to 910 nm to 950 nm.

  The laser beams of multiple wavelengths λ1, λ2, λ3,..., Λn are controlled by group (block) management for each wavelength band, for example. The output can be variably adjusted individually for each wavelength band. Moreover, the output of all the wavelength bands can be adjusted so that it may become the desired absorption rate to a workpiece | work.

In the cutting process, LD3 ₁ , 3 ₂ , 3 ₃ ,... 3 _n are simultaneously operated, and an appropriate assist gas such as oxygen or nitrogen is blown near the focal position. Thereby, the laser beams of the respective wavelengths from the respective LDs cooperate with each other and also with the assist gas such as oxygen to melt the workpiece at a high speed. Further, the molten work material is blown off by the assist gas, and the work is cut at a high speed.

The spectral beam combining unit 50 includes a fixing unit 51 that bundles and fixes the emission ends of the fibers 4 ₁ , 4 ₂ , 4 ₃ ,... 4 _n to form a fiber array 4, and fibers 4 ₁ , 4 ₂ , 4 _3. ,... 4 _n Collimator lens 52 that collimates laser light from _n , Diffraction grating 53 that diffracts multi-wavelength λ1, λ2, λ3,. And a condensing lens 54 that condenses the laser light from 53 and enters the transmission fiber 12. Incidentally, the diffraction grating 53, between the condenser lens 54, LD units _{3 1,} 3 2, _{3 3,} partially reflective coupler forming a resonator together with a reflecting surface provided on · · · _{3 n} trailing portion 55 is provided. The partial reflection coupler 55 is preferably disposed between the collimator lens 52 and the condenser lens 54.

  Referring to FIG. 1 again, in such processing such as cutting by the laser processing machine 13, the beam waist for each wavelength of the laser light of multiple wavelengths λ1, λ2, λ3,. It is about -400 μm, and multifocals are formed with these plural diameters. The beam waist is formed by an optical element having an incident diameter of the condenser lens 18 of about 2 mm to 20 mm and a focal length of 50 mm to 300 mm. The plate thickness of the workpiece W is, for example, about 0.5 mm to 30 mm. In the variable output adjustment of the laser oscillator 11 for each wavelength or each wavelength band, the output of the short wavelength side wavelength band is made larger than the long wavelength side output in the range where the incident angle is larger than 0 ° and smaller than 50 °. Can do. The cutting speed of the workpiece W can be selected in the range of 60 m / min to 250 m / min, for example.

(Sheet metal cutting method)
Hereinafter, a sheet metal processing method according to an embodiment of the present invention for processing a sheet metal having a thickness of 1 mm to 50 mm using the laser processing machine will be described.

1. First processing method This processing method is a method of cutting a sheet metal having a thickness of 2 mm or more, and has a focal length f ≧ 150 mm, and the focal position Pf is −2.0 mm <Pf with respect to the upper surface of the sheet metal. Using a condensing lens arranged at ≦ about 0.0 mm, the sheet metal is irradiated with parallel laser light from a DDL module.

  According to the method, a sheet metal having a thickness of 2 mm or more can be cut at a high speed (for example, a speed of 3 m / min to 6 m / min), and dross that can be easily removed is generated on the cut surface. Only.

  Here, the sheet metal is preferably an aluminum sheet metal.

  The laser light from the DDL module preferably includes two or more multi-wavelength laser lights, and the wavelength of each laser light is preferably less than 1000 nm.

  More preferably, the laser beam has a wavelength of 800 nm to 990 nm.

  The laser beam emitted from the DDL module or the BPP (beam parameter product) of the laser beam is preferably 7 mm * mrad or more and 20 mm * mrad or less.

  For example, the BPP is 10.3 mm * mrad.

  The beam waist (diameter) of the laser light is preferably 150 μm or more and 370 μm or less.

  More preferably, the beam waist is not less than 300 μm and not more than 364 μm.

  The Rayleigh length of the laser beam is preferably 1.5 mm or more and 6 mm or less, more preferably 2.2 mm or more and 3.4 mm or less.

2. Second Processing Method A second embodiment of the sheet metal processing method is a method of processing a sheet metal having a thickness of less than 2 mm, having a focal distance f of 120 mm or less, and a focal position Pf on the upper surface of the sheet metal. The sheet metal is irradiated with parallel laser light from the DDL module using a condenser lens set to 0.0 mm to 2.0 mm as a reference.

According to the above method, a sheet metal (aluminum) having a thickness of, for example, 1 mm can be cut at a high speed (for example, a speed of 14 m / min) without generating dross.
The gas pressure of the assist gas supplied to the processing point during the processing is preferably 0.8 MPa to 1.5 MPa, and more preferably 0.8 MPa to 1.2 MPa.

  Optical parameters such as the wavelength of the laser light from the DDL module, BPP, Rayleigh length, beam waist, and the like are the same as those in the first processing method.

  Hereinafter, examples of the embodiment will be described.

  In the following examples, unless otherwise specified, the output of the laser oscillator is 2 kW, and the incident angle of the laser beam on the aluminum plate as the workpiece (workpiece) is 70 °. As the multi-wavelength laser light, laser light having a wavelength of 910 mm to 950 nm was used.

1. Index of processing evaluation In this embodiment, the index of processing evaluation is such that the dross does not occur as shown in FIG. Determine.

  Note that “dross” refers to a substance in which a material melted by a laser beam at the time of cutting a material adheres as a molten material to the lower part of the material in the case of thermal cutting.

  As a result of laser cutting, the cut surface is in a state as shown in FIGS.

FIG. 4 shows a case where dross is generated in aluminum cutting, and the dross is easily peeled off by hand and the dross state is slight (hereinafter referred to as “light dross” and indicated by symbol “◯”).

  FIG. 5 shows a case in which dross is generated during aluminum cutting, and this dross can be peeled off by hand, but can be easily peeled off by using a tool (hereinafter referred to as a normal dross symbol ◯ Δ). FIG. 6 shows a state in which dross is generated in cutting aluminum, and this dross cannot be removed without using a tool (hereinafter referred to as heavy dross, indicated by symbol Δ). In this case, it can be understood that the height of the dross is larger than those in FIGS.

Therefore, the following indicators are adopted.
1) No dross: ◎
2) Light dross (dross that can be easily peeled by hand): ○
3) Normal dross (dross that can be easily dropped with a file such as a file): ○ △
4) Heavy dross (dross welded to the extent that it must be scraped: △
5) Unprocessable: ×

2. Example 1
FIG. 7 shows the test results of Example 1.

  In this example, the thickness of the workpiece (aluminum) was 1.0 mm, the focal length of the collimator lens was 100 mm, and the focal length of the condenser lens was 120 mm.

  The assist gas was nitrogen (N2), the pressure was 0.8 MPa, the nozzle was 2 mm in diameter, and GP (nozzle gap, which is the distance between the nozzle tip and the material) was 0.5 mm.

  As can be seen from FIG. 7, in Example 1, light dross cutting was realized when the focus was set at a position 0.5 mm to 2.0 mm above the workpiece upper surface.

  Furthermore, when the focal position was set to 0.5 mm to 1.5 mm from the upper surface of the workpiece, the workpiece could be cut at a speed of 14 m / min in a light dross state.

  More specifically, the upper limit of the focal position for realizing light dross cutting is 1.7% (2/120), preferably 0.8%, based on the focal length (120 mm) of the condenser lens. (1/120), and the lower limit is 0.0%.

  As already mentioned, in the table of FIG. 7, the ○ mark means a light dross that can be easily peeled by hand, and the ○ △ mark indicates a normal dross (which can be easily removed with a file such as a file) ) Signifies a heavy dross that must be scraped off, and a cross sign signifies that processing is impossible.

  Therefore, according to Example 1, the aluminum plate having a thickness of 1 mm uses a condensing lens with a focal length of 120 mm, and the focal point is set to a position 0.5 mm to 2.0 mm above the workpiece upper surface, thereby 14 m / mm. It can be seen that light dross can be cut at a processing speed of a minute.

3. Example 2
FIG. 8 shows the test results of Example 2.

  In this example, the thickness of the aluminum plate as a workpiece was 2 mm, the focal length of the collimator lens was 100 mm, and the focal length of the condenser lens was 150 mm.

  The pressure of nitrogen as the assist gas was 1.2 MPa, and the nozzle diameter was 2 mm.

  As understood from FIG. 8, in Example 2, light dross cutting was realized when the focal point was set at a position of +0.5 mm to −3.0 mm with respect to the workpiece upper surface.

In particular, the aluminum workpiece could be cut at a speed of 6 m / min by setting the focal position to 0 mm to +0.5 mm with respect to the workpiece upper surface.

  More specifically, the upper limit of the focal position for realizing light dross cutting is 0.3% (0,5 / 150) with reference to the focal length (150 mm) of the condenser lens, and the lower limit is − 2.0% (-3/150), preferably -1.3% (-2.0 / 150), more preferably -0.7% (-1/150), more preferably 0%. is there.

  Therefore, according to Example 2, the aluminum plate having a thickness of 2 mm uses a condensing lens with a focal length of 150 mm, and the focal point is set to a position 0.5 mm to 2.0 mm above the workpiece upper surface, thereby 14 m / It can be seen that light dross can be cut at a processing speed of a minute. Note that 0.5 mm is 0.3% of the focal length of 150 mm, and the focal position can be expressed as 0.3% of the focal length of 150 mm.

4). Example 3
FIG. 9 shows the test results of Example 3.

  In this embodiment, an aluminum workpiece having a thickness of 3 mm is processed using a collimator similar to the above and a condensing lens having a focal length of 150 mm.

  The pressure of the assist gas (nitrogen) was 1.5 MPa, and the gas nozzle diameter was 2 mm.

  As can be seen from FIG. 9, in Example 3, light dross cutting was realized by setting the focal position of the condenser lens to 0.0 mm to -1.5 mm with respect to the work upper surface. In particular, light dross cutting could be realized at a speed of 3 m / min by setting the focal position to -0.5 mm to -1.0 mm with respect to the upper surface of the workpiece.

  More specifically, the upper limit of the focal position for realizing light dross cutting is 0.0% (0.0 / 150) based on the focal length (150 mm) of the condensing lens, and more preferably −0.0. The lower limit is −1.0% (−1.5 / 150), preferably −0.7% (−1/150).

5. Comparative Example 1
FIG. 10 shows the test results of Comparative Example 1.

  In this example, an aluminum material having a thickness of 2 mm is cut using a collimator similar to the above and a condensing lens having a focal length of 120 mm.

  As understood from FIG. 10, in Comparative Example 1, light dross could be cut by setting the focal position to −0.5 mm to −0.2 mm with respect to the workpiece upper surface. Compared with 2 (FIG. 8), the cutting speed decreased to 5 m / min.

  From this, it is understood that a condensing lens having a focal length of 150 mm is more desirable than a condensing lens having a focal length of 120 mm for cutting a workpiece having a thickness of 2 mm.

6). Comparative Example 2
When an aluminum material having a thickness of 2 mm was cut using a fiber laser and a condensing lens having a focal length of 150 mm, it was found that heavy dross was generated regardless of the selection of the focal position.

  Thus, it is understood that the DDL laser is superior to the fiber laser in terms of dross adhesion.

Claims (14)

  When cutting a sheet metal having a thickness of 2 mm or more, a condensing lens having a focal length f ≧ 150 mm and a focal position Pf arranged at −2.0 mm <Pf ≦ about 0.0 mm with respect to the upper surface of the sheet metal. In the case where the sheet metal is irradiated with the parallel laser light from the DDL module and the sheet metal having a thickness of less than 2 mm is cut, the focal length f is f ≦ 120 mm, and the focal position Pf is A sheet metal processing method of irradiating the sheet metal with a parallel laser beam from a DDL module using a condensing lens arranged at 0.0 mm <Pf ≦ 2.0 mm with respect to the upper surface.   The sheet metal processing method according to claim 1, wherein the gas pressure of the assist gas supplied to the processing point at the time of cutting is 1.5 MPa (megapascal) or more.   3. The sheet metal processing method according to claim 1, wherein the laser light from the DDL module is composed of at least two or more multiple-wavelength laser lights, and the wavelength of any of the laser lights is less than 1000 nm.   The sheet metal processing method according to any one of claims 1 to 3, wherein a wavelength (Wavelength) of laser light from the DDL module is configured to be a multiple-wavelength of 800 nm to 990 nm.   The sheet metal processing method according to any one of claims 1 to 4, wherein a BPP (Beam parameter product) of laser light emitted from the DDL module is 7 mm * mrad or more and 20 mm * mrad or less.   6. The sheet metal processing method according to claim 1, wherein the laser beam has a Rayleigh length of 1.5 mm to 6 mm.   A method of cutting a thin sheet metal having a thickness of 1 mm, which has a focal length f of f ≦ 120 mm, and a focal position Pf arranged at 0.0 mm <Pf ≦ 2.0 mm with respect to the upper surface of the sheet metal. A sheet metal processing method of irradiating the sheet metal with laser light from a DDL module using a lens and processing at a processing speed of 3 to 6 (m / min).   The sheet metal processing method according to any one of claims 1 to 7, wherein a gas pressure of the assist gas supplied to the processing point is 0.8 MPa to 1.5 MPa. A method of cutting an aluminum sheet metal having a thickness of 2 mm, which has a focal length f ≧ 150 mm, and has a focal position Pf arranged at −2.0 mm <Pf ≦ about 0.0 mm with respect to the upper surface of the sheet metal. A sheet metal cutting method in which a laser beam from a DDL module is irradiated to the sheet metal using a lens and is processed at a processing speed of 3 to 5 (m / min).   9. The sheet metal processing method according to claim 1, wherein the sheet metal is an aluminum sheet metal. A DDL module that oscillates multi-wavelength laser light, a transmission fiber that transmits multi-wavelength laser light from the DDL module, and a laser that processes the sheet metal by condensing the multi-wavelength laser light transmitted by the transmission fiber A processing machine,
When cutting a sheet metal having a thickness of 2 mm or more, a condensing lens having a focal length f ≧ 150 mm and a focal position Pf arranged at −2.0 mm <Pf ≦ about 0.0 mm with respect to the upper surface of the sheet metal is used. A laser processing machine for irradiating the sheet metal with parallel laser light from a DDL module.   A method of cutting an aluminum sheet metal having a thickness of 3 mm, which has a focal length f ≧ 150 mm, and has a focal position Pf arranged at −1.0 mm <Pf ≦ −0.5 mm with respect to the upper surface of the sheet metal. A sheet metal cutting method for irradiating the sheet metal with a laser beam from a DDL module.   The sheet metal cutting method according to claim 12, wherein the sheet metal is processed at a processing speed of 2.5 to 3 (m / min). A method of cutting an aluminum sheet metal having a thickness of 2 mm or more,
When cutting an aluminum sheet metal having a thickness of 2 mm, a condensing lens having a focal length f ≧ 150 mm and a focal position Pf of 0.0 mm <Pf ≦ about 0.5 mm with respect to the upper surface of the sheet metal is used.
When cutting an aluminum sheet metal having a thickness of 3 mm, a condensing lens having a focal length f ≧ 150 mm and a focal position Pf arranged at −1.0 mm <Pf ≦ −0.5 mm with respect to the upper surface of the sheet metal is used. And
A sheet metal cutting method for irradiating the sheet metal with laser light from a DDL module.